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arXiv · 1410.6237

Synchrotron X-ray Diffraction Study of Structural Phase Transition in Ca10(Ir4As8)(Fe2-xIrxAs2)

Naoyuki Katayama·Kento Sugawara·Yuki Sugiyama·Takafumi Higuchi·Kazutaka Kudo·Daisuke Mitsuoka·Takashi Mizokawa·Minoru Nohara·Hiroshi Sawa
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Abstract

We report a structural transition found in Ca10(Ir4As8)(Fe2-xIrxAs2)5, which exhibits superconductivity at 16 K. The c-axis parameter is doubled below a structural transition temperature of approximately 100 K, while the tetragonal symmetry with space group P4/n (No.85) is unchanged at all temperatures measured. Our synchrotron x-ray diffraction study clearly shows iridium ions at a non-coplanar position shift along the z-direction at the structural phase transition. We discuss that the iridium displacements affect superconductivity in Fe2As2 layers.

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Naoyuki Katayama, Kento Sugawara, Yuki Sugiyama, Takafumi Higuchi, Kazutaka Kudo, Daisuke Mitsuoka, Takashi Mizokawa, Minoru Nohara, Hiroshi Sawa. 2014-10-23. Synchrotron X-ray Diffraction Study of Structural Phase Transition in Ca10(Ir4As8)(Fe2-xIrxAs2). https://doi.org/10.7566/jpsj.83.113707

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